That is plant fiber, used to differentiate from synthetic fibers, animal fibers, or mineral fibers. It consists of cells that have lost their growth function in plants, primarily composed of cellulose, a polymer of glucose macromolecules with the molecular formula (C6H10O5)n, while other fibers do not belong to this category.

Cellulose fibers refer to all fibers derived from cellulose polymers, which can be categorized into natural cellulose fibers, natural regenerated cellulose fibers, and modified regenerated cellulose fibers. Natural cellulose fibers primarily include cotton, ramie, and flax. Regenerated cellulose fibers are mainly viscose, acetate, and bamboo fibers.

Cellulose fibers offer superior skin contact, wearing comfort, physiological safety, moisture absorption, ease of processing, and biodegradability in their products, a range of characteristics that synthetic fibers cannot fully possess. As a result, nonwoven fabrics made from cellulose fibers find unique applications in medical, nursing, hygiene products, cosmetics, and other industrial sectors. In developed countries like Europe, America, and Japan, cellulose fibers have become an important raw material for nonwoven fabrics and are widely utilized. Biodegradable cellulose fibers include cotton fibers, viscose fibers, acetate cellulose fibers, and Lyocell fibers.